Thread-controlling mechanism for sewing-machines



i. BERGER, JR,

THREAD CONTROLLING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED 050,30. 1916.

1,3813% Patented June 14,1921.

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J. BERGER, JR.

IHREADBONTHOLUNG MECHAMSM FOR SEWING MACHINES.

APPLlCATlON men DEC. 30. 1916.

1,381,160 Patented June 14, 1921.

J, BERGER, in. I THREAD CONTROLUHG MECHANIS??? FOR SEWWG MACHINES.

APPUCATHOH HLED DEC 30 I915,

4 SHEETS-SH 1. BERGER, 1R. THREAD CONTROLLING MECHANISM FOR SEWING MACHiNES APPLICAT IO N FILED DEC- 30, 1916.

PatentefiJune 14, 1921.

4 SHEETSSHEET 4.

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J' OSEEH BERGER, JR., OF UTICA, NEW YORK, ASSIGNOR TO UNION SPECIAL'MACHINE COMPANY, OF UTIGA, NEW YORK, A CORPORATION OF NEW YORK.

THREAD-CONTROLLING MECHANISM' FOR SEWING MACI-IINES.,

Specification of Letters Patent.

Patented June 14, 1921.

Application filed December 30, 1916. Serial No. 139,825.

To all whom it may concern-I Be it known that I, J OSEPH BERGER, Jr., a citizen of the United States, residing at Utica, in the county of Oneida, State of New York, have invented certain new and useful Improvements in Thread-Controlling Mechanism for Sewing-Machines, of which the following is a description, reference being had to the accompanying drawing and to the figures of reference marked thereon.

The'invention relates to new and useful improvements in a thread controlling mechanism for sewing machines and more particularly to a mechanism for controlling the'needle threads in a multiple needle single looper stitching mechanism.

In a two needle machine having a single looper it is customary to set the needles so that the needle eye of the needle farthest from the looper when said looper is retracted is lower than the eye of the other needle. In a three needle machine with a single looper the eye of the farthest needle is lower than the eye of the middle needle and the eye of the needle nearest the looper, when retracted, is higher than the eye of the middle needle.

An object of the present invention is to provide a thread controlling mechanism for a stitch forming mechanism of the above character, which thread controlling mechanism will supply the proper amount of thread for each needle depending upon the distance that the eye of the needle passes beneath the material.

In the drawings which show byway of illustration one embodiment of the invention:

Figure 1 is a side view of the upper part of a. sewing machine having my improved thread controlling mechanism applied thereto, the needles being at their extreme upper position. 7

Fig. 2 is a similar view, but with the needles at their extreme lower position.

Fig. 3 is a plan view of the. same.

Fig. 4: is a detached perspective view showing the needle bar with a thread guide carried thereby, thethread guides carried by the needle lever and the stationary thread guide.

Fig. 5 is a transverse sectional View through the needle lever about the overhanging armshowing the fixed thread guide and the movable thread guides'cooperating therethread.

with when the needle lever is'at the upper end of its stroke.

Fig. 6 is a similar view, but showing the needle lever at the lower end of its stroke.

Our improved thread controlling mechanlsm is especially adapted for a sewingmachine having two or more needles with which a single looper cooperates. It is well understood that in this type of machine the needle eyes should beset so that the'needle farthest from the looper when retracted has its eye the lowest, thenext needle has its eye a little higher and if'three needles are used then the next needle, that is the one nearest the looper when retracted, has its eye the highest. The purpose of this is to secure a proper timing between the point of the looper and the needles so'thatthe looper will with certainty enter each needle loop in turn. In'othjer words, ifthe looper is set so as to cross the needle just above its eye, then the eye of the second needle must be set a little lower in order to give time for the looper point to reach the needle after having entered the first needle loop and likewise thefthird needle must be set still a little lower to give time forthe point of the looper to reachthe needle and cross the needle just above its eye. In a construction of this character it will be apparout that the needle eyes of the several needles will move different distances bfclow'the material being stitched; therefore, ifall three of the needles be given the same amount of slack thread and the parts timed so that the middle needle properly cooperates with the looper .in making a tight stitch, then the first needle which does not take so much slack thread would makea 'loosestitch, while the last needle; that is the needle farthest from the looper point when the looper is retracted, will require so much thread as to either break the thread through 'the tension placed thereon with the downward movement of the needle eye,' or cause thethread to cut through the fabric through the excessive pull of the needle on the respective needles will'be of uniform tightness; This is accomplished'by pullinga'little more thread from the supply for the needle which is farthest from the looper when retracted, than is pulled from thesupply for the other needles and it is further accomplished by taking up a little more of g the needle thread in the needle which is nearest the looper when retracted than is taken up for the other needle-s, In other words, the thread controlling mechanism may be properly adjusted or set for forming a stitch of desired tightness with the middle needle, and auxiliary devices are used ing machine having an overhanging arm 1 in which a needle bar 2 reciprocates. Theneedle bar is reciprocated by aneedle lever3 which is connected to the needle bar by a link 4:. The

needle bar is provided with three needles 5,

6 and 7. These needles are set abreast, that y is, in a line substantially at right angles to thellne of feed. Cooperating w1th the three needles beneath the worksupport is asingle looper 8, The mechanism for operating the looper may be ofthe usual character and has not therefore been disclosed. The work support 1s indlcatedat 9 1n the drawings.

' The eye lOof the needlefi is set at a lower point than the eye 11 of the needle 6 and the eye 11 of the needle 6 is also at a lower point than the eye 12 of the needle 7. in other words, the eyes ofthe needles are in a line which is inclined to the longitudinal axis of the needle bar. The purpose of this has been referred to above, that is, to enable the point of the looper 8ito cross each needle in turn at a point just above the eye of the needle so that the loopcr will with certainty engage each of the needle loops one after the other. It will be noted that when the eyes of the needles are set, as above stated, that the eye of the needle 5 will move a greater distance beneath the work support 9 than the eye of needle 6 and the eye of the needle 7, When the needle eye moves beneath the work support the prev1ous loops shed from the looper. are

drawn up and the stitch set. In order to accomplish this the threads must be drawn taut by this downward movement of the eye of the needle. If uniform stitches, therefore, are to be made by. each needle, the needle 5 must have a littlemore thread given to it than the needle (iand the needle 7 have a little less thread given to it than to the needle 6. I i

The thread for the needle 5is indicated at 5, the thread for the needle 6 is indicated at 6* and the thread for the needle 7 is indicated at 7*. The threads are led fromthe V through suitable tensions which.

are-mounted on a bracket13. From the tensions the threads areledjthrough thread guides 14-, thence between clamping disks 15, there being a pair of clamping disks for each thread, and thence "through thread guides 16. From the thread'guides 16 the threads are led through thread eyes in an arm 17 which is fixed to the overhanging arm 1 of the machine. The arm 17 is carried by a shank 18 which extends into a socket 19 formed in the, overhanginglarm and said shank is secured in place bya set screw20. The arm 17 is inclined downwardly toward its outer end and is formed with three spaced thread eyes 21, 22 and 28. The thread 5 passes through the thread eye 21';

the thread 6 passes through the thread eye 22 and the thread 7 passes through the thread eye 28 Fr om these thread eyes the thread passes through suitable eyes in an arm 24% carried by the needle lever and thence through thread eyes in an arm 25 carried'by the'needle lever. The arm 25 has, a thread eye 26 for the thread 5, an eye 2'? for the thread 6 and an eye 28 for the thread 7.

These thread e es are arran ed at different heights, as clearly shown in'l igs. 1, 2 and t of the drawings. The needle threads,

after passing through the thread eyes in the arm 25., are led through thread eyesin an arm 29 carried at the upper end of the needle bar and thence suitable eyes in the needle supporting collar 30 and thence through the eyes oflthe needles. An arm 31 is fixed to the needle lever and moves up and down therewith. The upper end of this arm is bent and posltioned so as to engage the needle threadfh only. Said arm 31, I when the needle lever moves downwardly, moves away from a line passing through the thread guides 1a and the tension devices; and, consequently, 011i the downward movement of the needle lever this arm will pull the threac 5 through its tension from the "supply. The thread clamping disks may be of any desired character, and, in fact, may

be omitted from' the machine, if desired,

and, therefore, they have not been. described in detail.

An arm 32, carriedby the overhanging arm of the machine, is disposed so as to engage the needle thread 7* only on the downward movement ofythe needle lever. The thread eyes in the arm 29 carried by theneedle bar move "below this arm 32 and said armwill therefore serve as a means for set, as above noted, at different heights. As

, taking up some ofthe needle thread? and th s insures the, needle '7 forming a tight st1tch. The thread eyes 26, 27 and 28v are a consequence the eye 26 willtake up less thread'than the eye 27, whilethe eye 27 takes up less thread than the eye 28. The thread fi passes throughthe eye 26 and, therefore, thi thread eye will take up less slack from the needle thread of the needle 5 and consequently said needle 5 will have more thread given to it on its downward movement than the needle 6.

The arm 17, as above noted, extends clownwardly. The thread 5* passes through the eye 21, while the thread 6 passes through the eye 22 and the thread 7 passes through the eye 23. Vhen the needle bar moves upwardly the arm 24, with its thread eyes, moves to a certain distance above the arm 17; therefore, thread will be at this time pulled through the thread clamping disks and from the supply. Inasmuch as the arm 21 moves a greater distance above the thread eye 21 than above the thread eye 22 more thread will be pulled off for the needle 5 than is pulled off for the needle 6, and less thread will be pulled off for the needle 7 than is pulled off for the needle 6. The ZLIIlil 31, as above noted, also pulls on the thread 5 pulling slack from the supply and these combined features result in giving ample thread to the needle 5 on its downward movement so as to prevent the needle from placing the thread under such great strain as to cut the fabric, or cause the thread to break. These devices also cooperate in giving less thread to the needle 7 than is given to the needle 6, which results in the needle 7 forming a tight stitch, and the stitches of all the needles being uniform. It is understood, of course, that the thread pulled oif by the arm 24 moving above the thread eyes in the arm 17 is given up to the needles on the downward movement of the needle lever and at the time when the needles are reaching the lower end of their stroke. The thread arm 17 is adjustable vertically and this changes the position of the thread eyes 21, 22 and 23 and thus varies the amount of thread drawn off for the respective needles.

It is obvious that minor changes in the details of construction and the arrangement of parts may be made without departing from the spirit of the invention as set forth in the appended claims.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is 1. The combination of a needle bar, a plurality of needles carried thereby, a needle lever, thread eyes carried by the needle lever, a fixed thread arm having thread eyes for the needle threads, said arm being inclined to the plane of the needle lever whereby the movable thread eyes carried by the needle lever will pull 0's and give up different amounts in the respective threads.

2. The combination of a needle bar, a plurality of needles carried thereby, a needle lever, thread eyes carried by the needle lever, a fixed thread arm having thread eyes for the needle threads, said arm being in clined to the plane of the needle lever whereby the movable thread eyes carried by the needle lever will pull off and give up different amounts in the respective threads, said fixed thread arm being adjustable for varying the amount of thread pulled off and given up. v

In testimony whereof I affix my signature in the presence of two witnesses.

JOSEPH BERGER, JR.

Witnesses A. J. BAEGHLE, ARTHUR L. lVILCOX. 

